Perhaps you should try some spelling variations:
thieu quang » thien quan, trien quang, hieu quan
thanh trung » thanh tung
hieu quang » hieu quan, hieu qua, diep quang
cua trong » cua truong, qua trong, ca trong
cua trung » cua truong, xuan trung, cua nhung
cong tan » cong tac, cong san, cong thanh
tan than » tan thanh, tan tran, ban than
than cau » toan cau, phan cau, than cap

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc ((hieu quang) or (thieu quang)) - thanh trung ((cua trong) OR (cua trung)) cong tan than cau~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc ((hieu quang) OR (thieu quang)) - thanh trung ((cua trong) OR (cua trung)) cong tan than cau.
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc ((hieu quang) or (thieu quang)) - thanh trung ((cua trong) OR (cua trung)) cong tan than cau".
• Adding a wildcard symbol may retrieve word variants: hoc ((hieu quang) or (thieu quang)) - thanh trung ((cua trong) OR (cua trung)) cong tan than cau*.